An electronic element in wide use usually has a body and a pin (also known as a lead, an outlet, a guide, a negative/positive terminal, and a negative/positive lead wire) connected to the body. Electronic elements of this kind include, but are not limited to, resistors, capacitors, inductors, diodes, and transistors. The pin is electrically connected to the body of the electronic element and a circuit board. The strength of the bonding between the body and the pin of the electronic element is a factor in the stability of electrical connection of the circuit board and therefore is a factor in the use and quality of electronic products. Hence, manufacturing processes of various electronic elements entail conducting a pin strength tension test thereon to make sure that the electronic elements thus manufactured meet product requirements and verification standards—for example, even when subjected to a specific tension, the body and the pin of the electronic element do not separate, nor does the pin sever.
The bonding strength between the body and the pin of the electronic element depends on the process flow of a manufacturing process thereof. Take an electrolytic capacitor as an example, the manufacturing process thereof comprises: (1) a nailing step: coupling an anode foil and the pin, followed by coupling a cathode foil and the pin, both by nailing or riveting, to form a positive pin and a negative pin which are exposed from the body of the electrolytic capacitor; (2) a winding step: positioning an electrolytic paper between the anode foil and the cathode foil, wherein the electrolytic paper is wound and fixed in place; (3) an immersing step: the electrolytic paper absorbs an electrolyte so as to form a dielectric disposed between an anode and a cathode; (4) an assembling and sealing step: covering the electrolytic capacitor with an aluminum casing, mounting a rubber lid thereon, protruding the pin out of the rubber lid, and hermetically sealing the electrolytic capacitor with a plastic film; and (5) a pin-cutting and tape-affixing processing step. The nailing step, the winding step, and the assembling and sealing step are the crucial steps in determining the bonding strength between the body and the pin of the electrolytic capacitor. Hence, it is necessary to perform a pin strength tension test so as to ensure that the electronic element will meet product requirements and verification standards.
Referring to FIG. 1, there is shown a schematic view of a conventional tension testing device for use with a pin strength tension test. As shown in FIG. 1, a tension testing device 1 comprises a base 10, a supporting member 12, a carrying member 14, a tensiometer 20, and a clamp 15. The tension testing device 1 is for performing a tension test on a body 102 and a pin 104 of an electronic element 100 to evaluate the bonding strength between the body 102 and the pin 104. The supporting member 12 is fixed in position on the base 10 and provided with the carrying member 14 whose position is adjustable. The carrying member 14 is for carrying the tensiometer 20 and adjusting the height of the tensiometer 20. The clamp 15 is for clamping the body 102 in a manner that the pin 104 points at the tensiometer 20 so as for the tension test to be conducted. When performed by means of the tension testing device 1, the tension test comprises the steps of: (1) welding the pin 104 and a test lead 110 together, wherein a hook portion 112 is formed at the other end of the test lead 110; (2) hanging the hook portion 112 of the test lead 110 at the tensiometer 20, followed by clamping the body 102 with the clamp 15; (3) starting the tensiometer 20, setting a preset tension level and a duration of continuity thereof, and performing the tension test; and (4) unwelding the pin 104 and the test lead 110 as soon as the tension test is done.
However, according to the prior art, it is necessary to weld the pin 104 and the test lead 110 together before performing a tension test with the conventional tension testing device 1. The welding process causes thermal stress to develop in the pin 104 to the detriment of the material strength of the pin 104. Also, external stress is produced in the step of clamping the body 102 with the clamp 15, thereby deforming the body 102 to the detriment of its appearance and even its internal structure. Furthermore, the step of clamping the body 102 with the clamp 15 is not quantified in terms of a clamping force and position, thereby resulting in a lack of consistency of a parameter in a plurality of instances of the tension test and therefore a negative effect on the accuracy of the result of the tension test. Also, the welding process performed on the test lead 110 contributes to a component of force derived from the applied tension, thereby deforming or bending the pin 104; with the deformed or bent pin 104 being no longer vertical, no tension can be fully applied to the electronic element 100. Last but not least, the step of hanging the hook portion 112 of the test lead 110 at the tensiometer 20 has a drawback: unless the body 102, the pin 104, the test lead 110, and the hook portion 112 are aligned, a component of force which is not vertical will derive from the applied tension.
In conclusion, a conventional tension testing device is likely to compromise the appearance of an electronic element under test, create a force component derived from an applied tension to thereby affect the tension test result, and render the tension test complicated, inconvenient, and inefficient. Accordingly, it is imperative to provide a pin tension testing device that features ease of use, enhances the stability of a test procedure, and yields a reliable tension test result, thereby enhancing the efficiency of production and the quality of products.